This invention relates to a vest for use by medical personnel during the course of surgery and to a system with which the vest may be used.
Medical operating room environments are maintained at a relatively cool temperature to keep the operating room staff comfortable. However, a comfortable temperature for the surgeon and support staff is not always the best temperature for the patient who can suffer hypothermia in a cold operating room environment. One remedy for this problem is to warm the patent with a disposable, heated blanket. In some cases, excessive heat is still lost from the patient at the actual site of the operation. On the other hand, if the operating room were kept at a warmer temperature, patient temperature could be maintained at a proper level, but the surgeons would be uncomfortably hot as would be operating room staff.
One proposed solution to the problem is to provide a cooling garment for the surgeon and/or operating room staff. One such garment consists of cooling water tubes sewn into a compliant vest of open mesh fabric worn next to the skin of the wearing. Cooling water from the existing operating room chiller flows through the tubes to carry away heat and keep the surgeon comfortable while the open mesh fabric of which the vest is made allows perspiration to escape. However, the complexity of the construction of such a garment makes the manufacturing cost excessive. Moreover, the cost factor is exacerbated as several sizes of the garment are required to fit the full range of body sizes of the wearers of the garment. In addition, the spacing between the tubes provides uneven heat transfer from the user""s skin.
Another such garment alternatively used to cool race car drivers consists of two layers of thermoplastic membrane material heat sealed together to form a serpentine flow path for cooling water. The pressure of the water inflates the passages to allow flow. This geometry reduces the cost of the vest, but the nature of the membrane material, particularly when inflated with cooling water, does not allow full compliance of the vest to the body curvature of the wearer. Moreover, the non-permeable nature of the membrane severely impedes the evaporation of perspiration from the skin of the wearer.
Furthermore, these garments can pose an additional hazard for the patient. The coolant is pumped through the garment to a coolant reservoir forming part of the operating room chiller. The latter is at atmospheric pressure and in order to cause flow of the coolant, the pump elevates the pressure of the coolant to induce flow. As a result, the coolant within the garment and associated conduits is at a pressure somewhat above atmospheric pressure. In the event the system springs a leak, it is possible that the coolant, which might not be sterile, could spray on the surgeon causing a distraction. Even more significantly, the coolant may spray on the patient in the area of the site of the operation giving rise to the possibility of infection or the like.
The present invention is directed to overcoming one or more of the problems.
It is a principal object of the invention to provide a new and improved cooling vest for use by medical personnel during surgical procedures. It is also a principal object of the invention to provide a system, including a cooling vest, that eliminates the possibility of leakage of coolant from the vest and the consequences that flow therefrom.
According to one facet of the invention, there is provided a cooling vest for medical personnel that includes a vest body having a top opening for the head of a wearer and opposed side openings for the arms of the wearer. The vest body includes at least two flexible membranes sealed to each other to define a coolant receiving space. At least one coolant inlet is provided to the space along with at least one coolant outlet. A coolant permeable, flexible spacer is disposed between the membranes within the space for preventing the membranes from collapsing upon one another.
In one embodiment of the invention, the spacer is a thin layer of flexible open celled foam.
In another embodiment, the spacer includes at least one flexible, generally helical coil. Still another embodiment of the invention contemplates that the spacer include at least one flexible grid. By way of example, plastic hexagonal mesh is one such material.
In a highly preferred embodiment, the vest consists of a single vest panel including the membranes, the coolant outlet, the coolant inlet and the flexible spacer. Alternatively, an alternate embodiment contemplates that the vest comprise at least two panels with each of the panels including the membranes, the coolant outlet, the coolant inlet and the flexible spacer. In the preferred embodiment, adjustable straps employing velcro, buckles, or the like, interconnects parts of the single vest panel in an adjustable fashion to allow the same to be sized to fit wearers of varying statures. In this embodiment, adjustment straps are located at the chest area of the panel, its sides and at the front. In the alternate embodiment, the adjustable straps interconnect the various panels to form the vest body so that one vest body may be sized to fit wearers of varying statures.
In both embodiments, the invention contemplates that some of the straps be connected to the respective panel parts or the individual panels inwardly of the adjacent sides or tops thereof so that the sides or tops of adjacent panel parts or adjacent panels may overlap to accommodate a wearer of small stature.
The preferred embodiment of the invention contemplates that the membranes be formed of a semi-permeable material as for example, the stretched, polytetrafluoroethylene film containing minute pores, an example of which is sold under the registered trademark xe2x80x9cGORE-TEXxe2x80x9d. This material allows moisture in gaseous form to pass through the film to thereby be drawn away from the skin of the wearer. It is also a two way stretch material, allowing the vest to readily conform to the body of the wearer, even when the vest panel or panels contain coolant.
A preferred embodiment includes an interior, membrane separating structure. Preferably, the same is a multi-layer, hexagonal plastic net separation structure. The same may also include an interior, adhesive membrane sealant line or lines to channel coolant flow in a desired flow path.
In the alternate form of the invention, as mentioned previously, plural vest panels are employed in the preferred form of the alternate embodiment and includes first, second and third panels. The first panel is a U-shaped top panel and the second and third panels are right side and left side panels respectively. The right and left side panels are connected, at their tops, to the right and left-hand sides of both the forward edge and a rearward edge of the first panel while the left and right sides of the right panel are connected respectively to the right and left side of the left side panel.
In the alternate embodiment, there are plural ones of the inlet spaced from one another and a coolant distributor interconnects the inlets. Similarly, in the alternate embodiment, there are plural ones of the outlet spaced from one another and the vest further includes a coolant collection manifold interconnecting the outlets.
In an alternate embodiment, the collection manifold and/or the distributor include a flexible tube located within the space between the membranes.
According to another facet of the invention, a cooling system for medical personnel for use during surgery is provided. The system includes a vest adapted to be worn by medical personnel to cover the torso and includes a top opening for disposition about the neck of the wearer and two oppositely directed, side openings for receipt of the arms of the wearer. A sealed, coolant receiving space is disposed within the vest and defines a flow path within the vest through which coolant may pass. The space has at least one inlet and at least one outlet. Also provided is a source of liquid coolant at ambient pressure connected to the inlet and a suction producing device connected to the outlet. The suction producing device draws coolant from the source through the space within the vest at sub-atmospheric pressure and returns the coolant to the source. As a consequence of this construction, should a leak come into existence, coolant will not leak to the exterior of the vest. Rather, ambient air, which does not affect operation, will be drawn into the coolant flow path.
In one embodiment, the flow path includes at least one tube. In another embodiment, the vest includes at least two flexible membranes sealed to each other to define the space and the flow path.
In a preferred embodiment the membranes are semi-permeable, allowing perspiration to be drawn away from the wearer into the coolant flow path.
In a highly preferred embodiment of the invention, the suction producing device includes an ejector. Preferably, the ejector includes a first inlet connected to the coolant source and an outlet also connected to the coolant source. A pump is provided for pumping coolant from the source to the first inlet. A second inlet is located between the first inlet and the ejector outlet and is connected to the outlet of the vest. As a consequence, the ejector creates a negative pressure at the second inlet to draw coolant at sub-ambient pressure through the vest.
Another embodiment contemplates a suction producing device in the form of a pump wherein the outlet of the pump is connected to the source of coolant and the inlet or suction side of the pump is connected to the vest outlet.
Other objects and advantages will become apparent from the following specification taken in connection with the accompanying drawings.